body {
    background-image: url("./pic/1080107.jpg");
    background-size: cover;
    background-repeat: no-repeat;
}

#title {
    color: #fff;
    text-shadow: 1px 1px 2px #000;
}

tr {
    background-color: aliceblue;
    opacity: 0.7;
}

tr:hover {
    background-color: lightseagreen;
}

#table_div {
    width: 90%;
    text-align: center;
    margin: 0 auto;
}

table {
    width: 100%;
    font-family: 'Noto Sans SC', sans-serif;
}

#header_div {
    width: 90%;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

#btn:active {
    transform: scaleY(0.9);
    color: #fff;
    background-color: cadetblue;
}